Skyrim:Respawning

Most locations in the game are respawning. This happens, depending on the location, at scheduled times. When a game location respawns, its enemies and loot are reset. This allows revisiting previously visited locations, which will have their contents reset. Specifically:

New versions are generated of all respawning enemies. They may not behave the same way as before, e. g. scripted conversations will usually not fire again.

The contents of any respawning containers are reset; this includes most chests and sacks. Any items previously stored in the respawned container are permanently deleted from the game.

New copies are generated for most items sitting out in the open (ingredients, books, clutter, etc.). If the previous copy is still in the game location, it is removed.

All activators will reset. Certain doors will re-lock, and any "quick exit" doors that were "barred from the other side" will be rebarred. However already opened dragon claw puzzle doors will not re-lock, and any keys you may have picked up the first time will still work.

The level of the location is set at the first visit, based on your current level. This means that the level of the enemies and the loot will be the same when you return to that location. When an area is too difficult to complete at the current level, you can return to location later when you have leveled to try again.

There are three different schedules that can be used for respawning a game location:

Never. Some dungeons are flagged as "Never Resets", which means that no matter how long you wait the contents are never altered. All containers in such locations are safe for long-term storage. This setting only applies to interior areas; any exterior areas associated with a never-respawning dungeon will respawn after 10 days. Examples of the areas that don't respawn are the houses that you can buy.

10 days (240 hours) of in-game time. This is the default time period used before a dungeon or any other game location respawns.

30 days (720 hours) of in-game time. This is the time period used if a dungeon has been cleared.

For any area to respawn, you must not enter the area during the specified time period. Each time you enter the area, the respawn clock is reset. Conversely, you can intentionally re-enter an area frequently to prevent storage containers from resetting (although you run the risk of losing everything if you forget to return in time).